Frank had purchased an engine stand, like this one ,pictured above, from some auto parts store years ago.
well last night Frank was moving an engine mounted on that stand and one of the cheap swivel casters locked up in small flaw in the garage floor,the result was the engine fell, and frank without thinking in that instant, tried hard to stop it from falling , and sprained his arm rather badly and barely missed crushing his foot!
every engine crane and engine stand Ive ever seen came with crappy steel wheels about 2.5"-3"in diam. but you have options (yes this mod adds $80-$120 to the cost of the engine stand) how much do you save by loosing a toe or breaking a foot keeping the cheap crappy castershttp://www.harborfreight.com/8-inch-...ake-46819.htmlhttp://www.northerntool.com/shop/too...5217_200305217a decent engine stand with decent casters is a far safer tool, and yes both the engine stans shown below need better casters added, but at least they are semi safer designs than the upper engine stand shownhttp://www.harborfreight.com/2000-lb...9521-8970.html

So instead of blaming the root causes, being a damaged floor and debris on the floor, you blame the engine stand?
That's like blaming the spoon for making someone fat.

your missing the point here!
NO engine stand design that is safe too use should have a tendency to tip simply because it has a caster wheel roll over a dropped wrench, or hit a floor seam or some other common shop floor hazard, a properly designed engine stand with decent size swivel casters easily takes that type of obstacle in stride, it should remain stable and have no tendency to tip over. its just not that expensive or difficult to select a decent engine stand and go to the minimal effort required to install decent size and quality casters, that make moving the engine stand with the engine mounted far easier and safer and with far less of a tendency to tip even if it does hit some object on the floor.
yes It does take some extra effort , or expense to buy and install the larger casters or select a engine stand design with a wide base that is far more stable to begin with.
yes we all make choices and price is obviously one factor, but saving $100 or so and working with an engine stand thats inherently unstable is in my opinion a poor choice

each of us is free to make our own choices , but having an engine fall and potentially injure me is one I can most likely avoid
while price alone is not always a good indicator of quality its usually a good bet that the smaller and cheaper engine stands with the smaller wheel bases, like this

are harder to tip once the engines mounted, due to simple leverage and physics

and that every engine stand Ive seen for sale for under $300 has had really crappy low quality and small diameter casters, and few have caster roll locks, the main point I was trying to make here was that upgrading the casters to the larger size, and better quality and selecting an engine stand with a wide stable base to convert to the use of those larger swivel casters makes it far less likely to be effected by running over minor trash, or floor seams.

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if you can,t smoke the tires at will from a 60mph roll your engine needs more work

only time i have had a problem was when i wasnt paying attention to what i was doing..
IE like your friend was not doing when pushing the engine stand.
brother stole/borrowed/took back the ~1000lb engine stand i was using... while it handled my duramax and BBC engine you go definitely tell it was putting a strain on it..
it was this style of a standhttp://www.jegs.com/i/JEGS+Performan...80040/10002/-1
drove down to jegs and picked this up..http://www.jegs.com/i/JEGS+Performan...80041/10002/-1
rolls on my roughed concrete floor(use house livestock) nicely

While were talking about the larger shop tools here, If you don,t have a swivel hook,or engine leveler/tilter, trust me it makes the job far easier, to have both
once you do youll wonder why you ever attempted the job without those accessories, without the swivel hook the engine constantly wants to swing back to one location, it fights you constantly, the tilter makes clearing and indexing the engine angle so much easier
buy the 1.5-2 ton rated hook for your engine hoist and grease the swivel center pin on the hookhttp://www.mfrexpress.com/alloy-swiv...ton-p-699.html
adding a swivel like this between the leveler and crane GREATLY AIDS THE ENGINES REMOVAL, DON,T GET STUPID or CHEAP, GET THE 3000lb-3500lb rated one not the 1200lb size (REMEMBER YOULL BE UNDER THAT ENGINE SOMETIMES)
the picture above can be used as a teaching aid, this guys got the engine tilter he needs but its mounted with the tilter too far above the carburetor, limiting the distance the engine can be lifted above the fenders there should be about 2"-3" between the carburetor BASE MOUNT ON THE INTAKE, tilter at most,with the carb removed and the intake opening duct taped closed and lower edge of the engine, intake carburetor mounting pad and having the distributor still installed is still a small risk, that, is best avoided as it could be damaged, its best removed for safety, but the picture also does not have the swivel,hook, and hes using it with the crank handle at the wrong end as it will hit the wind shield in some applications while cranking in that location, rather than having the crank face the crane like it should http://www.mfrexpress.com/alloy-swiv...ton-p-699.htmlI think youll find a properly installed swivel hook increases the cranes lift distance as the hook loop can be supported by the bolt thru the crane beam or a screw link and hooked directly into the engine leveler,either option is likely too be shorter than the current few chain links, IN ANY CASE ITS AN OPTION ALMOST ALL MY FRIENDS, AND I , NOW SWEAR BY AS A MANDATORY ACCESSORY if you get a spare $20 or so, and have the time to order one, I think youll find its money well spent.

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if you can,t smoke the tires at will from a 60mph roll your engine needs more work